An apparatus separating a resonance excitation response of a first disc from a resonance excitation response of second disc, the apparatus includes spindle motor with a spindle motor hub supporting the first disc, a disc spacer communicating with the first disc supporting a second disc and a clamp ring attached to this on the motor hub imparting a clamping force on the second disc to form a disc pack. Separation of resonance response between the first disc and the second disc results from maintaining a distinction between an amount of extension of mass and stiffness of each disc available for resonance excitation beyond respective outboard clamping points of the disc spacer. Separation of resonance assures resonance of the first disc is dissipated by a damping of the spindle motor, as well as resonance of the second disc is dissipated by the damping of the spindle motor.